The present invention relates to a method and system for providing multipoint gaseous fuel injection to an internal combustion engine for use in various vehicles and engine-powered machines and more particularly, to a method and system for electrically controlling an engine operating on gasoline and alternative fuels.
Alternative fuels such as natural gas, hydrogen, propane, and ethanol are starting to enter the market in the transportation sector. This is due to a number of factors, including lower price, reduced tailpipe emissions, and the security of the fuel supply in comparison to gasoline and diesel fuel. Furthermore, natural gas and propane reduce greenhouse gas (GHG) emissions by about 25% compared to gasoline in automotive applications, while ethanol can reduce GHG emissions by about 30% to 65% depending on the process used to produce the ethanol. Similarly, hydrogen fuelled vehicles can reduce GHG emissions by about 60% to 80%.
Providing systems and methods to enable efficient and productive use of alternative fuels is required.
In accordance with one aspect of the present invention there is provided a method of modifying a fuel injection signal having a pulse width, the fuel injection signal being provided by a controller managing a fuel powered apparatus receiving gasoline and an alternative fuel for electrical control of a gasoline operated injector and an alternative-fuel operated injector, the controller having information on temperature, exhaust gas oxygen (EGO) content, air-fuel ratio, fuel trims and a control system type, the method comprising: (a) receiving the pulse width of the fuel injection signal; (b) receiving the information on the temperature, the EGO content, and the fuel trims; (c) modifying the pulse width of the fuel injection signal based on the received information, the modified pulse width controlling alternative fuel supplied by the alternative fuel injector to the fuel powered apparatus; (d) determining whether an error criterion is met based on measured information of the fuel powered apparatus operating on the alternative fuel and desired response information; and (e) repeating the steps (c) and (d) when the error criterion is not met.
In accordance with another aspect of the present invention there is provided a system for modifying a fuel injection signal having a pulse width, the fuel injection signal being provided by a controller managing a fuel powered apparatus receiving gasoline and an alternative fuel for electrical control of a gasoline operated injector and an alternative-fuel operated injector, the controller having information on temperature, exhaust gas oxygen (EGO) content, air-fuel ratio, fuel trims and a control system type, the system comprising: a mechanism constructed and adapted to obtain the pulse width of the fuel injection signal; a mechanism constructed and adapted to receive the information on the temperature, EGO content and the fuel trims; a mechanism constructed and adapted to modify the pulse width of the fuel injection signal based on the received information, the modified pulse width controlling the alternative fuel supplied by the alternative fuel injector to the fuel powered apparatus; and a mechanism constructed and adapted to determine whether an error criterion is met based on measured information of the fuel powered apparatus operating on the alternative fuel and desired response information.
In accordance with another aspect of the present invention there is provided a system for controlling fuel injection of an internal combustion engine of a vehicle, the system comprising: sensors applied to the vehicle for sensing parameters relating to the vehicle and the fuel injection; a controller for providing a fuel injection signal having a pulse width based on the sensed parameters; a fuel injector for injecting a first fuel in a first mode and a second fuel in a second mode into the engine; a comparator for comparing the sensed parameters with reference parameters to provide an error signal; a pulse width modifier for changing the pulse width in response to the error signal; and a switch for providing the fuel injection signal to the fuel injector and the pulse width modifier in the first and second modes, where: in the first mode, the fuel injector injects the first fuel into the engine in response to the pulse width of the fuel injection signal, in the second mode, the fuel injector injects the second fuel into the engine in response to a modified pulse width of a modified fuel injection signal, the modified pulse width being one changed by the pulse width modifier, the parameters sensed by the sensors in the second mode being provided to the comparator, the comparator providing the error signal in comparing the sensed parameters to the reference parameters.
In accordance with another aspect of the present invention there is provided a vehicle having an internal combustion engine comprising first and second groups of fuel injectors, the first group of injectors being gasoline injectors, the second group of injectors being alternative fuel injectors; the vehicle comprising: sensing means for providing information on air for use in the engine, engine temperature, and exhaust gas oxygen content; control means for providing a fuel control signal having a pulse width in response to the information provided by the sensing means; means for selecting a path of the fuel control signal; first fuel injection means for controlling the gasoline injection by the gasoline injectors in response to the pulse width of the fuel control signal, while the path of the fuel control signal is selected to the first fuel injection means; pulse modification means for modifying the pulse width of the fuel control signal when the path of the fuel control signal is selected to the pulse modification means; and second fuel injection means for controlling the alternative fuel injection by the alternative fuel injectors in response to a modified pulse width of the fuel control signal.
In accordance with another aspect of the present invention there is provided a computer program product comprising a computer useable medium having computer logic stored therein for modifying a fuel injection signal having a pulse width, the fuel injection signal being provided by a controller managing a fuel powered apparatus receiving gasoline and an alternative fuel for electrical control of a gasoline operated injector and an alternative-fuel operated injector, the controller having information on temperature, exhaust gas oxygen (EGO) content, air-fuel ratio, fuel trims and a control system type, the computer program product including: a mechanism constructed and adapted to obtain the pulse width of the fuel injection signal; a mechanism constructed and adapted to receive the information on the temperature, EGO content and the fuel trims; a mechanism constructed and adapted to modify the pulse width of the fuel injection signal based on the received information, the modified pulse width controlling the alternative fuel supplied by the alternative fuel injector to the fuel powered apparatus; and a mechanism constructed and adapted to determine whether an error criterion is met based on measured information of the fuel powered apparatus operating on the alternative fuel and desired response information.
In accordance with another aspect of the present invention there is provided a computer-readable media tangibly embodying a program of instructions executable by a computer to perform a method of modifying a fuel injection signal having a pulse width, the fuel injection signal being provided by a controller managing a fuel powered apparatus receiving gasoline and an alternative fuel for electrical control of a gasoline operated injector and an alternative-fuel operated injector, the controller having information on temperature, exhaust gas oxygen (EGO) content, air-fuel ratio and fuel trims, the method comprising: (a) receiving the pulse width of the fuel injection signal; (b) receiving the information on the temperature, EGO content, and the fuel trims; (c) modifying the pulse width of the fuel injection signal based on the received information, the modified pulse width controlling the alternative fuel supplied by the alternative fuel injector to the fuel powered apparatus; (d) determining whether an error criterion is met based on measured information of the fuel powered apparatus operating on the alternative fuel and desired response information; and (e) repeating the steps (c) and (d) when the error criterion is not met.
In accordance with another aspect of the present invention there is provided, in a vehicle controller, in which a fuel injection signal having a pulse width is modified, the fuel injection signal being provided by the vehicle controller managing a fuel powered apparatus receiving gasoline and an alternative fuel for electrical control of a gasoline operated injector and an alternative-fuel operated injector, the controller having information on temperature, exhaust gas oxygen (EGO) content, air-fuel ratio and fuel trims, a memory medium comprising software programmed to provide the modified fuel injection signal by a method comprising: (a) receiving the pulse width of the fuel injection signal; (b) receiving the information on the temperature, EGO content, and the fuel trims; (c) modifying the pulse width of the fuel injection signal based on the received information, the modified pulse width controlling the alternative fuel supplied by the alternative fuel injector to the fuel powered apparatus; (d) determining whether an error criterion is met based on measured information of the fuel powered apparatus operating on the alternative fuel and desired response information; and (e) repeating the steps (c) and (d) when the error criterion is not met.
In an exemplary embodiment, the step of modifying the pulse width can be performed by a separate microprocessor from the powertrain controller. The separate microprocessor receives various signals from the engine and outputs the pulse width for the alternative fuel. In some cases the microprocessor affects control over the powertrain controller by modifying the gasoline pulse width for the alternative fuel while preventing the fuel trims on the powertrain controller from saturating. In other cases the powertrain controller affects control over the microprocessor by utilizing the fuel trims from the powertain controller to control the pulse width.
For example, the alternative fuel is natural gas and thus, the engine operates on gasoline and/or natural gas. In the method for modifying a fuel injection signal, as the measured information, a value of an EGO content while the engine is operating on the alternative fuel. Also, as the desired response information, a desired air-fuel ratio as the desired response information is provided. In response to the measured information and the desired response, the pulse width of the fuel injection signal provided by the powertrain controller is modified. The engine operating on alternative fuel is provided with the proper mixture of the alternative fuel and air to respond to various engine loads and meet emission standards.
For example, the alternative fuel is natural gas and thus, the engine operates in a bi-fuel manner, that is, gasoline or natural gas. In the system for modifying a fuel injection signal, a value of an EGO while the engine is operating on the alternative fuel is obtained and a desired air-fuel ratio is provided. In response to the value of the EGO and the desired air-fuel ratio, the pulse width of the fuel injection signal provided by the powertrain controller is modified. The engine operating on the alternative fuel is provided with the proper mixture of the alternative fuel and air to respond to various engine loads and meet emission standards.
For example, the alternative fuel is natural gas and thus, the engine operates in a bi-fuel manner, that is, gasoline or natural gas. The system modifies the pulse width of the fuel injection signal provided by the powertrain controller, in response to a value of an EGO or fuel trim signals while the engine is operating on the alternative fuel at the desired air-fuel ratio. Therefore, the engine operating on the alternative fuel is provided with the proper mixture of the alternative fuel and air.
For example, the alternative fuel is natural gas and thus, the engine operates in a bi-fuel manner, that is, gasoline or natural gas. The pulse modification means modifies the pulse width of the fuel control signal, in response to a value of an EGO while the engine is operating on the alternative fuel and the desired air-fuel ratio. In response to the modified pulse width, the second fuel injection means controls the alternative fuel injection of the second group of injectors. Therefore, the engine operating on the alternative fuel is provided with the proper mixture of the alternative fuel and air and the vehicle is operated on various engine load conditions and meets emission standards.